Refrigerating apparatus of the compression type



REFRIGERATING APPARATUS UF THE COMPRESSION TYPE Filed March 16, 1939 2 Sheets-Shea; 1

mm; Hug

Feb. 11, 1941- T E 2,231,162

REFRIGERATING APPARATUS OF THE COMPRESSION TYIE I Filed March 16, 1939 2 Sheets-Sheet 2 r W llia ill at least part of the separate pipe connections Patented Feb. 11,1941

UNITED STATES PATENT OFFICE ,REFRIGERATING APPARATUS OF THE COMPRESSION TYPE Application March 16,

1939, Se1'ial No. 262,143

In Germany March 17, 1938 10 Claims.

My invention relates to improvements in refrigerating apparatus of the compression type, in particular to refrigerators having a hermeticallysealed motor-compressor set.

It is known to simplify the manufacture of individual refrigerator elements, such as the condenser or the evaporator, by welding two corrugated metal sheets together in face-to-face relationship so that the condenser or evaporator conduits are formed by the corrugations. According to the prior art these individual condenser or evaporator elements are connected with each other and with the compressor by additional pipe connections.

An object of the present invention is to simplify the construction and'manufacture of refrigerating apparatus having an hermeticallysealed motor-compressor set by reducing the number of individual elements to be assembled. Another object, more particularly, is to eliminate heretofore necessary for interconnecting the various elements of a compression refrigerator system. An object also is to increase the amount of sheet metal work relative toother manufacturing operations required for compression refrigerators, so as to reduce a considerable portion of the manufacturing process to the stamping, bending, and welding of a few sheet metal pieces. Other objects of my invention deal with the design and arrangement of the compressor, condenser and evaporator elements relative to one another and relative to a refrigerator cabinet so as to obtain a simple yet reliable and thermally economical construction. I i

According to my invention, the housing, which hermetically encloses the motor-compressor set of a refrigerating apparatus, is at least partly formed of an indented and corrugated metal sheet which forms also part of a sheet metal condenser. According to the further invention, a considerable portion of the housing, the condenser, the evaporator and at least part of the interconnecting conduits are formed byindentations and corrugations of a singlepair of metal sheets welded together in face-to-face relationship. These and other features of my invention will become apparent from the following description of the embodiments diagrammatically illustrated in the drawings in which- Fig. 1 shows a part-sectional side elevation of a cabinet refrigerator according to the present invention, while i Fig. 2 shows a side elevation and Fig. 3 a front elevation of a sheet metal structure from which the refrigerating system proper of the embodiment of Fig. 1 is produced by bending the sheet pairs at the two places indicated in Figs. 2 and 3 by lines a--a and bb.

Fig. 4 illustrates another embodiment by a part-sectional side view, and

Figs. 5, 6 and 7 exemplify a third embodiment by a front elevation, a sectional top view and a sectional side elevation respectively.

Referring to Fig. 1, 60 is the cabinet of a do- 10 mestic refrigerator, and BI the cabinet door. The cabinet is supported by four legs 62 so as to provide space for the motor-compressor set below the cabinet. I denotes the driving motor of the set, 2 the piston compressor driven by the motor I. The motor-compressor set is arranged in a housing 6 attached to the leg structure of the refrigerator cabinet and is suspended by means of springs 4 from brackets 5 secured to the housing 6. The housing has a cover portion I so as to hermetically seal the motor-compressor set. To the motor shaft is secured an oil pump 8 which forces the lubricant contained in the lower part 9 of the cover I to the points of the set to be lubricated. l0 denotes a valve operating in response to the oil pressure. The valve establishes a communication between the suction side and the pressure side of the compressor until a given oil pressure is attained and thereby facilitates the starting of the refrigerating apparatus. This construction of the motor-compressor set is mentioned for illustrative purposes only, Motor-compressor sets of this type are described more in detail in my U. S. Patent No. 2,164,405 and do not form an essential part of the present invention as any other sealed motorcompressor type may also be used.

ll denotes the condenser of the refrigerating apparatus and I2 the evaporator. I3 is a. collecting vessel which may contain a regulating valve, for instance a fioat-controlled'valve, for controlling the supply of liquid refrigerant to the evaporator. A suction conduit M (Fig. 3) connects the evaporator I2 with the compressor. The compressed refrigerant leaves the compressor through a pressure conduit l5, passes into the air-cooled condenser ll, thence through a conduit Hi to the vessel l3, and then through a conduit l1 into'the evaporator. The arrangement thus includes a complete refrigerating circulation system.

, The evaporator l2, the condenser II, the vessel I3, and the conduits I4, l5 and I6, are all formed by indentations and corrugations of a single pair of metal sheets l8 and I9 placed in face-to-face relationship and secured together around their edges by welding. The sheet it forms at the same time also the cover 1 of the enclosure for sealing the motor-compressor set. The sheets l8 and I9 are bent when welded together about the bending edges a-a, bb into the form shown in Fig. 1, so that in the readyassem-bled refrigerator, the motor-compressor set lies underneath the cooling chamber and the evaporator l2 in the upper portion of the cooling chamber, whereas the condenser ll extends along the rear wall of the refrigerator. 20 denotes an ice tray placed on the plate-shaped evaporator. 2| and 22 (Fig. 3) are recesses cut out of the sheets [8 and I9 between the sheet sections forming the condenser H and the evaporator l2. These recesses reduce the metallic cross section of the sheet pair and thus prevent an undesirable transfer of heat from the condenser II to the evaporator I2. 23 (Fig. 1)

denotes a. plug consisting of insulating material which when assembling the refrigerator is inserted in an opening of the rear wall of the cabinet together with the sheet metal structure.

Fig. 4 shows a similar embodiment of the invention and denotes corresponding parts by the same reference numerals as in Figs, 1 to 3. The embodiment of Fig.4 differs from that shown in Fig. 1 in that the pair of sheets l8 and I9 is bent only once, namely about a bending edge corresponding to line b-b in Figs. 2 and 3, so that the cover I of the motor-compressor set lies substantially in the same plane as the condenser l I. Accordingly, the shaft of the motor-compressor set is horizontal in contrast to the vertical shaft arrangement of Fig. 1.

In Figs. 5 to 7, 3| denotes the driving motor and 32-the piston compressor of the motor-compressor set. The motor casing 33 is provided with projections 34 formed of angle iron which are supported by coil springs 35 hearing against angle irons 36 secured to the housing 63 of the motorcompressor set. The housing 63 is formed by indentations of two metal sheets 4! and 42 sealed face-to-face together. Other indentations of the metal sheets form the condenser and other elements to be later described. The lower end of the perpendicular motor shaft 31 is designed as an oil pump 38 as described in my aforementioned patent. This oil pump projects into the oil sump at the bottom of the motor-compressor housing. A conduit 49 and a sinuous winding 50 connect the oil pump 38 with an inlet opening 51 at the top of the housing 63. The lubricant thus is cooled in winding 50 before it reaches the moving parts to be lubricated. -Due to this circulation of the oil, the heat developed inside the motorcompressor housing is dissipated to the sheet metal walls 4i, 42 which are in direct contact with the cooling air. The condenser consists of a laterally extensive vessel 40 of flat shape surrounding the housing 63 of the motor-compressor set. The bottom portion of the condenser 40 opens into a chamber 43 for collecting the liquefied refrigerant. A conduit 44 consisting of a capillary tubewith helical portions 45 and 46 connects the collecting chamber 43 with the evaporator 41 (Fig. 7). A suction conduit 48 connects the evaporator 41 with the compressor.

In the embodiment shown in Figs. 5 to 7, the housing 63, the condenser 40, the condensate collecting chamber 43 and the oil circulating conduits 49 and 50 are all formed by indentations of the two metal sheets 4| and 42. Only the evaporator 41 and the two conduits connecting t e evaporator with the sheet metal structure consist of separate elements. The evaporator 41 according to Fig. 7 is secured to a heat insulating insert 64 of the cabinet wall 65.

When welding the two metal sheets forming the motor-compressor housing as well as the condenser and other elements according to the invention, itsuflices asa rule to weld the sheets around their outer edges and at some intermediate not-indented places, for instance as indicated in Figs. 3 and 5 by broken lines.

As exemplified by the above-described embodiments, the invention allows producing at least a substantial portion of the circulation system of a compression refrigerator from a single pair of indented metal sheets. A considerable part of the manufacturing thus can be done by sheet metal work such as stamping and pressing. The assembling of the refrigerating systems is simplified and limited to a small number of separate elements. As a great number of the operating vessels and conduits of the circulation system are formed by the metal sheets and thus automatically brought into proper relationship and connection with one another, the manufacture of refrigerators according to the invention is less exacting and involves fewer sources of possible faults than the manufacture of the known constructions. The invention, therefore, is especially advantageous for mass production.

I claim: 1

1. In a refrigerating apparatus of the compression type having a motor-compressor set sealed in a housing and connected with a condenser conduit system and an evaporator conduit system, said housing and at least one of said conduit systems being formed by indentations of a single pair of metal sheets sealed face-toface together.

2. In a refrigerating apparatus of the compression type having a compressor sealed in a housing and a condenser conduit system connected with; said compressor, in combination, said condenser comprising two corrugated metal sheets sealed face-to-face together so as to form the condenser conduits between said sheets, and said compressor housing and one of said metal sheets consisting of a single sheet metal piece.

3. In a refrigerating apparatus of the compression type having a motor-compressor set sealed in a housing, a condenser, an evaporator, and interconnecting conduits, a single pair of metal sheets sealed together in face-to-face relationship and having indentations and corrugationsforming said housing, said condenser, said evaporator, and said interconnecting conduits.

4. In a refrigerating apparatus of the compression type having a motor-compressor set sealed in a housing, a condenser, an evaporator, and interconnecting conduits, a single pair of metal sheets sealed together in face-to-face relationship and having indentations and corrugations forming asubstantial portion of said housing, said condenser, and said evaporator, said condenser and said evaporator being arranged in two different sections of said pair of sheets, said pairbeing bent at a right angle so as to have said sections in planes perpendicular to each other.

5. In a cabinet refrigerator having a cooling chamber, a motor-compressor set hermetically sealed in a housing, a condenser, an evaporator,

sisting of indented portions of a single pair of metal sheets welded together in face-to-face relationship, said pair of sheets being bent at a right angle, the sheet portion forming said condenser extending in parallel relation to one of the vertical walls of the cabinet, and the sheet portion forming the evaporator extending horizontally and projecting through said vertical cabinet wall into the upper portion of said cooling chamber.

6. In a refrigerating apparatus of the compression type having a motor-compressor set sealed in a housing, a condenser, an evaporator, and interconnecting conduits, a single pair of metal sheets sealed together in face-to-face relationship and having indentations and corrugations forming a substantial portion of said housing, said condenser and said evaporator, said pair of sheets having a reduced cross section between said evaporator and said condenser as compared with the cross section in other parts of said sheets so as to impede the transfer of heat from said con- 7 denser to said evaporator.

7. In a. refrigerator according to claim 5, said pair of metal sheets havinga cut-out recess near the bend between said horizontal sheet portion forming the evaporator and said vertical sheet portion forming the condenser, said recess being arranged within said cabinet wall so as to impede a heat transfer from the condenser into said cooling chamber.

8. In a. refrigerator having a compressor in a pressure-tight housing, a condenser, an evaporator, and interconnecting conduits arranged to form a. refrigerant circulation system, in combination, a pair of metal sheets of elongated shape welded face-to-face together, each having indentations in registry with indentations of the other sheet, said indentations forming said condenser,

evaporator and conduits, at least one of said sheets having another indentation forming part of said housing, said indentations which form said condenser extending laterally over the major portion of the width of said pair and having a longitudinal extension larger than said lateral extension so as to form an extensive flat vessel, said housing and said evaporator being arranged at opposite sides of said condenser near the ends of said oblong and connected with each other by a suction duct forming part of the aforesaid conduits and extending between said condenser and a longitudinal edge of said oblong.

9. In a refrigerator having a sealed motorcompressor set containing an oil pump, in combination, a pair of metal sheets welded together in face-to-face relationship and having an indented area forming a housing for said motorcompressor set, corrugations forming an aircooled oil circulation conduit outside said housing for connecting said pump with the top portion of said housing, and another indented area forming a condenser for the compressed refrigerant.

10. In a refrigerator having a sealed motorcompressor set containing an oil pump, in com- RUDOLF HIN'IZE. 

